000 A000000 04/30/2006 000 C000000 0000885601 000 D000000 N 000 E000000 NF 000 F000000 Y 000 G000000 Y 000 H000000 N 000 I000000 6.1 000 J000000 A 001 A000000 MS INSURED MUNICIPAL INCOME TRUST 001 B000000 811-06590 001 C000000 2127625260 002 A000000 1221 AVENUE OF THE AMERICAS 002 B000000 NEW YORK 002 C000000 NY 002 D010000 10020 003 000000 N 004 000000 N 005 000000 N 006 000000 N 007 A000000 N 007 B000000 0 008 A000001 MORGAN STANLEY INVESTMENT ADVISORS INC. 008 B000001 A 008 C000001 801-42061 008 D010001 NEW YORK 008 D020001 NY 008 D030001 10020 010 A000001 MORGAN STANLEY SERVICES COMPANY INC. 010 C010001 JERSEY CITY 010 C020001 NJ 010 C030001 07311 012 A000001 MORGAN STANLEY TRUST 012 B000001 84-5710 012 C010001 JERSEY CITY 012 C020001 NJ 012 C030001 07311 013 A000001 DELOITTE & TOUCHE LLP 013 B010001 NEW YORK 013 B020001 NY 013 B030001 10281 014 A000001 ARAB MALAYSIA SECURITIES 014 B000001 8-00000 014 A000002 CHINA INTERNATIONAL CAPITAL CORPORATION LTD 014 B000002 8-00000 014 A000003 HC SECURITIES 014 B000003 8-00000 014 A000004 JM MS FIXED INCOME SECURITIES PRIVATE LIMITED 014 B000004 8-00000 014 A000005 JM MORGAN STANLEY PRIVATE LIMITED 014 B000005 8-00000 014 A000006 JM MORGAN STANLEY SECURITIES PRIVATE LIMITED 014 B000006 8-00000 014 A000007 JM MORGAN STANLEY RETAIL SERVICES PRIVATE LTD 014 B000007 8-00000 014 A000008 MORGAN STANLEY & CO. INCORPORATED 014 B000008 8-15869 014 A000009 MORGAN STANLEY & CO. LIMITED 014 B000009 8-00000 014 A000010 MORGAN STANLEY ASIA LIMITED 014 B000010 8-00000 014 A000011 MORGAN STANLEY CANADA LIMITED 014 B000011 8-00000 014 A000012 MORGAN STANLEY QUILTER LIMITED 014 B000012 8-00000 014 A000013 MS DEAN WITTER AUSTRALIA SECURITIES LIMITED 014 B000013 8-00000 014 A000014 MORGAN STANLEY JAPAN LIMITED 014 B000014 8-00000 014 A000015 MORGAN STANLEY, S.V., S.A. 014 B000015 8-00000 014 A000016 MORGAN STANLEY DW INC. 014 B000016 8-14172 014 A000017 MORGAN STANLEY INTERNATIONAL LIMITED 014 B000017 8-00000 014 A000018 MORGAN STANLEY SECURITIES LIMITED 014 B000018 8-00000 014 A000019 MORGAN STANLEY BANK AG 014 B000019 8-00000 014 A000020 MORGAN STANLEY DISTRIBUTION INC. 014 B000020 8-44766 014 A000021 MORGAN STANLEY DISTRIBUTORS INC. 014 B000021 8-45262 014 A000022 MORGAN STANLEY MARKET PRODUCTS INC. 014 B000022 8-37795 014 A000023 MS SECURITIES SERVICES INC. 014 B000023 8-26804 014 A000024 PRIME DEALER SERVICES CORP. 014 B000024 8-47025 014 A000025 VAN KAMPEN FUNDS INC. 014 B000025 8-19412 015 A000001 THE BANK OF NEW YORK 015 B000001 C 015 C010001 NEW YORK 015 C020001 NY 015 C030001 10286 015 E010001 X 018 000000 Y 019 A000000 Y 019 B000000 105 019 C000000 MORGANSTAN 020 A000001 GOLDMAN, SACHS & CO. 020 B000001 13-5108880 020 C000001 7 020 C000002 0 020 C000003 0 020 C000004 0 020 C000005 0 020 C000006 0 020 C000007 0 020 C000008 0 020 C000009 0 020 C000010 0 021 000000 7 022 A000001 MORGAN GUARANTY TRUST CO. OF NEW YORK 022 B000001 13-3224016 022 C000001 35540 022 D000001 25240 022 A000002 MERILL LYNCH, PIERCE, FENNER & SMITH INC. 022 B000002 13-5674085 022 C000002 10400 022 D000002 10200 022 A000003 BEAR STEARNS & CO. INC. 022 B000003 13-3299429 022 C000003 6268 022 D000003 11306 022 A000004 GOLDMAN, SACHS & CO. 022 B000004 13-5108880 022 C000004 8380 022 D000004 7022 022 A000005 CITIGROUP GLOBAL MARKETS INC. 022 B000005 11-2418191 022 C000005 6368 022 D000005 4059 022 A000006 MORGAN (J.P.) SECURITIES INC. 022 B000006 13-3224016 022 C000006 0 022 D000006 8930 022 A000007 DAIN RAUSCHER INCORPORATED 022 B000007 41-1416330 022 C000007 0 022 D000007 5435 022 A000008 U,S, BANCORP PIPER JAFFRAY INC. 022 B000008 41-0953246 022 C000008 4676 022 D000008 0 022 A000009 KIRKPATRICK, PETTIS, SMITH, POLLIAN 022 B000009 47-0301070 022 C000009 4245 022 D000009 0 022 A000010 RAYMOND JAMES & ASSOCIATES, INC. 022 B000010 59-1237041 022 C000010 0 022 D000010 3408 023 C000000 80023 023 D000000 79982 024 000000 N 026 A000000 N 026 B000000 Y 026 C000000 N 026 D000000 Y 026 E000000 N 026 F000000 Y 026 G010000 N 026 G020000 N 026 H000000 N 027 000000 N 045 000000 Y 046 000000 N 047 000000 Y 048 000000 0.270 048 A010000 0 048 A020000 0.000 048 B010000 0 048 B020000 0.000 048 C010000 0 048 C020000 0.000 048 D010000 0 048 D020000 0.000 048 E010000 0 048 E020000 0.000 048 F010000 0 048 F020000 0.000 048 G010000 0 048 G020000 0.000 048 H010000 0 048 H020000 0.000 048 I010000 0 048 I020000 0.000 048 J010000 0 048 J020000 0.000 048 K010000 0 048 K020000 0.000 049 000000 N 050 000000 N 051 000000 N 052 000000 N 053 A000000 N 054 A000000 Y 054 B000000 Y 054 C000000 Y 054 D000000 N 054 E000000 N 054 F000000 N 054 G000000 Y 054 H000000 Y 054 I000000 N 054 J000000 Y 054 K000000 N 054 L000000 Y 054 M000000 Y 054 N000000 N 054 O000000 Y 055 A000000 N 055 B000000 N 056 000000 Y 057 000000 N 058 A000000 N 059 000000 Y 060 A000000 Y 060 B000000 Y 061 000000 0 062 A000000 Y 062 B000000 0.0 062 C000000 0.0 062 D000000 0.0 062 E000000 3.2 062 F000000 0.0 062 G000000 0.0 062 H000000 0.0 062 I000000 0.0 062 J000000 0.0 062 K000000 0.0 062 L000000 0.0 062 M000000 0.0 062 N000000 0.0 062 O000000 141.9 062 P000000 0.0 062 Q000000 0.0 062 R000000 0.0 063 A000000 0 063 B000000 18.2 064 A000000 Y 064 B000000 N 066 A000000 N 067 000000 N 068 A000000 N 068 B000000 N 069 000000 N 070 A010000 Y 070 A020000 N 070 B010000 N 070 B020000 N 070 C010000 Y 070 C020000 N 070 D010000 N 070 D020000 N 070 E010000 Y 070 E020000 Y 070 F010000 N 070 F020000 N 070 G010000 Y 070 G020000 N 070 H010000 N 070 H020000 N 070 I010000 N 070 I020000 N 070 J010000 Y 070 J020000 N 070 K010000 Y 070 K020000 N 070 L010000 N 070 L020000 N 070 M010000 N 070 M020000 N 070 N010000 Y 070 N020000 N 070 O010000 Y 070 O020000 N 070 P010000 Y 070 P020000 N 070 Q010000 N 070 Q020000 N 070 R010000 N 070 R020000 N 071 A000000 34083 071 B000000 43942 071 C000000 479738 071 D000000 7 072 A000000 6 072 B000000 11546 072 C000000 0 072 D000000 0 072 E000000 0 072 F000000 666 072 G000000 197 072 H000000 0 072 I000000 23 072 J000000 11 072 K000000 0 072 L000000 17 072 M000000 6 072 N000000 9 072 O000000 0 072 P000000 0 072 Q000000 0 072 R000000 24 072 S000000 13 072 T000000 0 072 U000000 0 072 V000000 0 072 W000000 328 072 X000000 1294 072 Y000000 11 072 Z000000 10263 072AA000000 2707 072BB000000 1829 072CC010000 0 072CC020000 2827 072DD010000 8888 072DD020000 1000 072EE000000 0 073 A010000 0.4050 073 A020000 0.0000 073 B000000 0.0453 073 C000000 0.0000 074 A000000 60 074 B000000 0 074 C000000 10700 074 D000000 474206 074 E000000 0 074 F000000 0 074 G000000 0 074 H000000 0 074 I000000 0 074 J000000 1029 074 K000000 0 074 L000000 8050 074 M000000 73 074 N000000 494118 074 O000000 4388 074 P000000 146 074 Q000000 0 074 R010000 0 074 R020000 0 074 R030000 0 074 R040000 308 074 S000000 155167 074 T000000 334109 074 U010000 21659 074 U020000 0 074 V010000 15.43 074 V020000 0.00 074 W000000 0.0000 074 X000000 3015 074 Y000000 280 075 A000000 0 075 B000000 340884 076 000000 14.53 077 A000000 Y 077 B000000 N 077 C000000 N 077 D000000 N 077 E000000 N 077 F000000 N 077 G000000 N 077 H000000 N 077 I000000 N 077 J000000 N 077 K000000 N 077 L000000 N 077 M000000 N 077 N000000 N 077 O000000 Y 077 P000000 N 077 Q010000 Y 077 Q020000 N 077 Q030000 N 078 000000 N 080 C000000 081 A000000 Y 081 B000000 104 082 A000000 N 082 B000000 0 083 A000000 N 083 B000000 0 084 A000000 N 084 B000000 0 085 A000000 Y 085 B000000 N 086 A010000 0 086 A020000 0 086 B010000 471 086 B020000 6699 086 C010000 0 086 C020000 0 086 D010000 0 086 D020000 0 086 E010000 0 086 E020000 0 086 F010000 0 086 F020000 0 087 A010000 SHARES OF BENEFICIAL INTEREST 087 A020000 61745P791 087 A030000 IIM 088 A000000 N 088 B000000 N 088 C000000 N 088 D000000 Y SIGNATURE Jennifer Jimenez TITLE